1. Field of the Invention
The present invention relates to electrophotographic toners for use with electrophotographic image-forming apparatus, such as copying machines and printers.
2. Description of the Prior Art
For an electrophotographic toner fixed by heating on paper, styrene-acrylic resins have been widely used which are produced by copolymerizing a styrene monomer, such as styrene, with an acrylic monomer, such as methyl acrylate.
However, since styrene-acrylic resins generally have low toughness, a toner comprised of such resin is liable to a trouble such that when a load is applied on stacked papers having a toner image fixed thereon so that friction was caused to the papers, some toner stain is caused to the back of an upper-side paper, or a so-called smear trouble.
The occurrence of such smear poses a problem in the case of, for example, double-side copying that is recently widely in practice for the purpose of resource saving, because it causes a stain to an image surface. Therefore, a need exists for an electrophotographic toner which is free from smear trouble, that is, a toner having good smear resistance.